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        Precision cold drawn pipe is a high-precision steel pipe material with good performance in terms of appearance, size and performance. However, when testing precision cold-drawn tubes, it is found that its hardness does not meet the standard requirements and is on the low side. What is the reason for this?
       During the production process of precision cold-drawn tubes, high-temperature salt bath furnaces are generally used for quenching and heating to achieve the deoxidation effect. However, complete deoxidation cannot be achieved in actual implementation. When it interacts with the carbon on the surface of precision cold-drawn tubes, insufficient hardness will occur.
      In addition, the cooling rate during the quenching process has an important impact onPrecision cold drawn tubeThe hardness should also be very large. Usually, the slower the cooling rate, the more the hardness of the product decreases. In order to avoid the occurrence of this kind of phenomenon, salt bath deoxidation must be strictly carried out, and the cooling temperature and time must be strictly controlled to achieve the best product.